1.Simulation of respiratory motion effect on dose distributions in three-dimensional radiotherapy
Zhenle FEI ; Zhenyang NIU ; Zhijie LI ; Lei WANG
Chinese Journal of Radiation Oncology 2012;(6):554-556
Objective To evaluate the effects of respiratory on dose distributions in threedimensional conformal radiotherapy (3 DCRT) and intensity-modulated radiotherapy (IMRT).Methods The dose distributions were measured with a PTW 2D-ARRAY seven29 placed on a home-made moving platform to simulate the respirator.Dosimetric comparisions for 3DCRT and IMRT plans were performed by means of Gamma analysis with 3% and 3 mm,respectively.Dose distribution measured for static treatment plans.Results The respiratory could reduce the target does and conformal index.The r pass rate (3%3 mm in 3 DCRT was greater than it in IMRT ((53.58 ± 0.74) %,(30.71 ± 1.00) %,t =57.91,P < 0.01).The failed points were mainly near the field edge,but located in the whole target volumes for IMRT plans.Conclusions It is undesirable to use IMRT techniques for tumors with large motion amplitude.3DCRT can give a reliable dose distribution by reasonably selecting the PTV margin.
2.Analysis of VMAT dosimetric verifications with different techniques
Zhenyang NIU ; Zhenle FEI ; Zongjin DUAN ; Zhijie LI ; Lei WANG
Chinese Journal of Radiation Oncology 2017;26(8):929-933
Objective To investigate the gamma (γ) passing rates for volumetric-modulated arc therapy (VMAT) dosimetric verification with different techniques.Methods A total of 12 VMAT plans for the treatment of different anatomical sites in cancer patients were chosen.The Octavius 4D system was used to measure the dose distributions in two different settings:the gantry was rotating (three-dimensional (3D) and 2D γ-analysis) and the gantry was fixed at 0°(2D γ-analysis).The γ passing rates were analyzed with 3%/3 mm and 2%/2 mm criteria, using the paired t test or Wilcoxon signed-rank test.The 2D γ passing rates for different irradiation methods were calculated.Results For the 3D and 2D dose distributions obtained at a rotating gantry angle as well as the 2D dose distribution obtained at zero gantry angle, the average γ passing rates were 96.03%, 96.98%, and 98.90% for 3%/3 mm (P=0.227, P=0.000, P=0.003);82.08%, 84.04%, and 90.90% for 2%/2 mm (P=0.379, P=0.000, P=0.000).For the 2D dose distributions obtained with different irradiation methods, the average γ passing rate was 98.99% for 3%/3 mm and 93.68% for 2%/2 mm.Conclusions The VMAT dosimetric verification based on a 3D volumetric dosimeter at a rotating gantry position can be clinically useful for delivery quality assurance (QA), and can achieve the most reliable dose calculation for VMAT, which has more referential values.
3.Application of detector array in treatment planning system modeling adjustment
Zhenyang NIU ; Zhenle FEI ; Zongjin DUAN ; Zhijie LI ; Lei WANG
Chinese Journal of Radiation Oncology 2017;26(7):806-809
Objective To investigate the feasibility of detector array in Monaco modeling for MLC parameters adjustment.Methods One parameter was fixed, and then the other parameter was changed.The γ pass rates of the test beams, namely 3ABUT, 7SegA, and FOUR L, were assessed to determine the values of leaf transmission and leaf offset.A total of 12 tumor cases from different anatomical sites were randomly selected.Two-dimensional dose verification (rack angle zero) of Step& Shot and dMLC plans as well as three-dimensional dose validation of VMAT plan were performed using Octavius 4D system.The γ pass rates were analyzed at a standard of 3%/3 mm.Meanwhile, the point dose verification for these three plans was analyzed to obtain the dose deviations.Results The values of leaf transmission and leaf offset were 0.0105 and-0.08 mm, respectively.The average γ pass rates (%) of Step& Shot, dMLC, and VMAT plans were 88.59±2.94, 87.81±3.28, and 87.45±2.24 before adjustment and 98.45±1.23, 98.9±1.01, and 96.03±1.66 after adjustment.In addition, the average dose deviations (%) according to the point dose verification were 0.85±0.75, 0.95±0.39, and 0.98±0.40 before adjustment and 0.97±0.57, 1.08±0.76, and 0.86±0.45 after adjustment.Conclusions Octavius detector 729 ionization chamber array is a feasible and reliable device in Monaco modeling for MLC parameters adjustment.
4.Clinical analysis of Mondini dysplasia with cerebrospinal fluid leakage and preliminary genetic research of it.
Lili WANG ; Yong FENG ; Zhijie NIU ; Yuxiang CAI ; Lingyun MEI ; Chufeng HE
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2015;29(10):874-877
OBJECTIVE:
To summarize and analyze the clinical characteristics of Mondini dysplasia with cerebrospinal fluid leakage, as well as preliminarily investigate the genetic mechanism of the disease.
METHOD:
The clinical data of 2 patients diagnosed as Mondini dysplasia with cerebrospinal fluid leakage treated in our hospital were analyzed. Blood samples of these two patients were obtained to extract DNA. We screened DNA samples for gene SLC26A4 mutations by using polymerase chain reaction and direct sequencing. The sequencing results were analyzed in DNASTAR software.
RESULT:
Both patients came to our hospital because of recurrent meningitis, and the fistula were both located in vestibular window. Patients were cured one-time after surgical closure of the leakages with temporalis + temporalis fascia + temporalis through the mastoid approach. No pathogenic mutations of gene SLC26A4 with exome sequencing were found.
CONCLUSION
Mondini dysplasia with cerebrospinal fluid leakage should be considered in patients with recurrent meningitis and hearing disorder. Temporal bone HRCT is helpful to the diagnosis. Surgical closure is an effective therapeutic method and may prevent recurrent meningitis. The molecular mechanism of simple Mondini dysplasia needs further study.
Cerebrospinal Fluid Leak
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physiopathology
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Cochlea
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pathology
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Fistula
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pathology
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Humans
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Hyperplasia
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genetics
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physiopathology
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Membrane Transport Proteins
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genetics
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Meningitis
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physiopathology
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Mutation
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Sulfate Transporters
5.The toxic and protective effects of Polygonum multiflorum on normal and liver injured rats based on the symptom-based prescription theory.
Jingyao PANG ; Zhaofang BAI ; Ming NIU ; Can TU ; Zhijie MA ; Yanling ZHAO ; Kuijun ZHAO ; Yun YOU ; Jiabo WANG ; Xiaohe XIAO
Acta Pharmaceutica Sinica 2015;50(8):973-9
The dosage-efficacy/toxicity relationship of the 50% alcohol extracts of Polygonum multiflorum was comparatively investigated on either normal or CCl4-induced chronic liver injury rats, by determining the general condition, serum biochemical indices and liver histopathology, coupled with the factor analysis. The dosages were 10 and 20 g raw materials per kg body weight. Compared with the normal control group, the normal high dose group showed significant increases of the serum alanine transaminase (ALT), total bilirubin (TBIL), high mobility group box 1 (HMGB-1) and interleukin-1β (IL-1β) (P < 0.05 or P < 0.01), as well the frequent incidences of inflammatory cell infiltration, hepatic sinus enlargement and fiber stripes formation in histopathological sections. Compared with the model control group, the model low dose group showed significant declines of serum ALT, aspartate transaminase (AST) and total bile acid (TBA) (P < 0.05), as well the alleviation of vacuoles of hepatocytes, but no amelioration of the inflammatory cell infiltration and fibrous tissue hyperplasia; moreover, the model high dose group showed significant degeneration declines of serum HMGB-1, tumor necrosis factor-α (TNF-α) and IL-1β (P < 0.05, P < 0.01), as well the evident alleviation of vacuoles degeneration of hepatocytes, inflammatory cells infiltration and fibrosis degree. The factor analysis showed that the low dosage treatment had almost neither injuring effect on the normal rats nor protective effect on the model rats; while the high dosage treatment showed observable injuring effect on the normal rats, expressed by the significant increases of the factor-1 (HMGB-1, TNF-α and IL-1β as the main contributors) and factor-2 (TBIL, ALT and TBA as the main contributors) relative to the normal control group. The liver protective effect of the high dosage treatment could be observed with the significant reduction of the factor-1, indicating the effective alleviation of the expression of inflammatory cytokines. In conclusion, it could illustrated the phenomenon of symptom-based prescription theory of Polygonum multiflorum on rat livers: the high dosage of the herb had either an injuring effect on normal rats, or a therapeutic effect on the rats with chronic liver injury.
6.The efficacy and safety of 125I seed implantation on the treatment of refractory thyroid carcinoma
Deyue YUAN ; Zhen GAO ; Zhijie YANG ; Sui DU ; Shulei NIU ; Hongtao ZHANG ; Juan WANG
Chinese Journal of Endocrine Surgery 2019;13(4):297-300
Objective To systematically evaluate the efficacy and safety of 125I seed implantation on the treatment of refractory thyroid carcinoma.Methods A total of 14 patients with refractory thyroid carcinoma received CT and ultrasound image-guided 125I seed implantation in our hospital from Apr.2003 to Oct.2016.The radioactive activity ranged from 0.3 to 0.8 mCi,and the prescribed doses were 80 to 120 Gy.11 patients were diagnosed as differentiated thyroid carcinoma and 3 patients were medullary thyroid carcinoma.The local control rate,pain relief and complications were observed.Results The patients were followed up from 12 to 96 months.Two months after treatment,complete remission happened in three patients,partial remission in nine,and disease stability in two,no patients with progression.The half year,one year,two year local control rate was 100%,92% and 42%,respectively.Seven patients were evaluated using number rating scales and obtained a score of 4.14±1.68 before therapy.Two months after treatment,the score was reduced to 2.00±1.15 (P<0.000).No usual complications occurred during or after treatment except for I acute skin radio reaction in 4 cases.Conclusion 125I seed interstitial implantation for refractory thyroid carcinoma under guidance of ultrasound or CT is efficient and safe.
7.Application of Monte Carlo simulation in radiation dose estimation and optimization for diagnostic radiology
Zhijie ZHANG ; Yantao NIU ; Lihua ZHU ; Baohua SUN
Chinese Journal of Radiological Medicine and Protection 2024;44(2):151-157
The increasing frequency of radiographic diagnostic imaging and the cumulative dose to the public from radiation has raised widespread concerns. However, accurate measurement of the radiation dose received by the human body is difficult to achieve. Monte Carlo simulation, as a numerical computational method guided by probability statistics theory, has been applied to various dose assessments, imaging optimizations, and radiation protection in radiographic diagnostic imaging. We provide a comprehensive review of the principles of the Monte Carlo method, the modelling process of Monte Carlo simulation and the progress of its application to diagnostic radiological dose estimation.
9.Pathogenesis and multidisciplinary management of medication-related osteonecrosis of the jaw.
Lina HE ; Xiangyu SUN ; Zhijie LIU ; Yanfen QIU ; Yumei NIU
International Journal of Oral Science 2020;12(1):30-30
Medication-related osteonecrosis of the jaw (MRONJ) is a serious side effect of bone-modifying agents and inhibits angiogenesis agents. Although the pathogenesis of MRONJ is not entirely clear, multiple factors may be involved in specific microenvironments. The TGF-β1 signalling pathway may have a key role in the development of MRONJ. According to the clinical stage, multiple variables should be considered when selecting the most appropriate treatment. Therefore, the prevention and management of treatment of MRONJ should be conducted in patient-centred multidisciplinary team collaborative networks with oncologists, dentists and dental specialists. This would comprise a closed responsibility treatment loop with all benefits directed to the patient. Thus, in the present review, we aimed to summarise the pathogenesis, risk factors, imaging features, clinical staging, therapeutic methods, prevention and treatment strategies associated with MRONJ, which may provide a reference that can inform preventive strategies and improve the quality of life for patients in the future.
Bisphosphonate-Associated Osteonecrosis of the Jaw/prevention & control*
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Bone Density Conservation Agents/adverse effects*
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Humans
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Quality of Life
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Risk Factors
10.Compatibility Mechanism of Mineral Medicine Os Draconis in Bupleuri Radix-containing Tri-herbal Medicines Based on Supramolecular Systems
Zi XING ; Junling HOU ; Yifan ZHAO ; Liman XIAO ; Mengjia WEI ; Mengyuan YANG ; Lu YUN ; Yuanfei NIU ; Zhijie ZHANG
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(14):191-198
ObjectiveBy starting with the combination of Os Draconis, Bupleuri Radix, and Ostreae Concha, the role of mineral medicine Os Draconis in the combination of the Bupleuri Radix-containing tri-herbal medicines was preliminarily explored from the perspective of supramolecular system formation. Method① The appearance and Tyndall phenomenon of single decoction of Os Draconis, Bupleuri Radix, and Ostreae Concha, as well as co-decoction of Bupleuri Radix-Os Draconis, Bupleuri Radix-Os Draconis-Ostreae Concha, and Bupleuri Radix-Ostreae Concha were observed, and the average particle size, dispersion coefficient, and Zeta potential of suspension particles in each decoction were determined. The micromorphology of supramolecular structures was observed by scanning electron microscope (SEM). ② The pH of different compatibility systems, liquid viscosity coefficient, liquid surface tension, freeze-dried powder yield rate, and other physical properties were determined, and the interaction of different compatibility systems was detected by infrared absorption spectroscopy (FTIR) and UV-visible spectrophotometry (UV-Vis). ③ The composition and content difference of different compatible systems were determined by high-performance liquid chromatography (HPLC) and ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF-MS). ResultCompared with the single decoction, the co-decoction had more obvious turbidity and Tyndall phenomenon. The particles in the co-decoction suspension were smaller and more evenly distributed, and the Zeta potential was reduced, indicating a more stable system. Under SEM, Bupleuri Radix was irregularly lamellar, and Bupleuri Radix-Os Draconis and Bupleuri Radix-Os Draconis-Ostreae Concha were mainly spherical nanoparticles. Bupleuri Radix-Ostreae Concha was irregularly lamellar, with a small number of spherical nanoparticles. The pH of the single decoction of Bupleuri Radix and co-decoction increased, and the viscosity coefficient increased. The liquid surface tension decreased. The freeze-dried powder yield rate of the Bupleuri Radix-Os Draconis co-decoction was the highest, followed by Bupleuri Radix-Ostreae Concha decoction and Bupleuri Radix-Os Draconis-Ostreae Concha decoction, and the yield rate of Bupleuri Radix single decoction was the lowest. The main change of FTIR was the stretching vibration of -OH, and the co-decoction moved to the low-frequency direction obviously. UV-Vis showed that the maximum absorption occurred at 295.8 nm for all groups, and the absorption intensity was different (Bupleuri Radix-Os Draconis>Bupleuri Radix-Os Draconis-Ostreae Concha>Bupleuri Radix-Ostreae Concha>Bupleuri Radix). The components of Bupleuri Radix were used as the indexes, and the content of methanol extract determined by HPLC was higher than that of water extract, and the components of Bupleuri Radix single decoction were mainly saikosaponin a (SSa) and saikosaponin c (SSc), which were slightly higher after co-decoction compatibility. UPLC-Q-TOF-MS could identify 37 compounds in both single decoction and co-decoction. ConclusionThe combination of Bupleuri Radix, Os Draconis, and Ostreae Concha can form a smaller, more uniform, and stable nano-sized supramolecular system, which is conducive to the dissolution of the main components of Bupleuri Radix, and the Os Draconis contributes the most in this process.